Typically for myself and other players, if you alt+tab out of the game and back in or press esc, once you're back into the game it will resume working fine, I don't know if the devs have seen and are working on it or not though many people are having this issue. I typically pause the game if I'm in a fight then get the mouse working again and unpause, otherwise you're guaranteed to die as pressing esc or tabbing out generally creates a lag spike that will freeze your game for a few seconds.